Edmund hunt



(No Model.) 2 Sheets-Sheet 2.

, E. HUNT.

DEVICE FOR DRIVING A HELIGAL SEWING NEEDLE. No. 294,627. Patented Mar.4, 1884.

FIG.2.

WW W UNITED STATES PATENT OFFICE.

EDMUND HUNT, OF GLASGOW, COUNTY OF LANARK, SCOTLAND.

DEVlCE FOR DRIVING A HELICAL SEWING-NEEDLE.

SPECIFICATION forming part of Letters Patent No. 294,627, dated March 4,1884,

Application filed December 5, 1883. (No model.) Faiented in England July17. 1878, No. 2,856; in France January 16, 1879, No. 128,474, and inGermany February 11, 1879, No. 9,802.

To all whom it may concern:

Be it known that I, EDMUND HUNT, a subjcct of the Queen of Great Britainand Ireland, and residing at Glasgow, in the county of Lanark, Scotland,have invented an Improved Device for Driving a Helical Sewing-Needle,(for which the following patents have been obtained, namely: British,dated July 17,1878, No. 2,856; French, dated January 16, 1879, No.128,474, and German, dated February 11, 1879, No. 9,802,) of which'thefollowing is a specification.

My invention relates to sewing-machines of the kind by which a thread(or combination of two or more threads acting as one thread) is laid ina helical form, and is made to pass round the edge or edges of the clothor material to be overcast or sewed together.

In Lain g s machine-which I believe to be the most successful of theearlier machines of the kind referred to, and'which is fully describedin the specification of Laings United States Patent, dated April 27,1875, No. 162,665- the needle is a smooth cylindrical helix frictionallydriven by means of a belt. This needle goes completely through thecloth, like the needle used in ordinarily sewing by hand, and cannottherefore befixed to any part of the machine.

. The object of my invention is to drive the needle in a positivemanner, notwithstanding that it is smooth or without notches or teeth. Iemploy helically-grooved pulleys to hold and drive the helical needle,and inasmuch as the needle, if made a cylindrical helix, would by theresistance to its passing through the cloth be made to creep orgradually slip out of its proper place betweencorrespondinglycylindrical helically-grooved pulleys, I make the needlein the form of a conical helix, and hold and drive it by means ofcorrespondingly-conical helically-grooved pulleys, forming what I termthe helicone driving arrangement. The axes of the conical needle anddriving-pulleys all converge to one point, and the arrangement is suchthat the resistance would tend to make the needle creep toward thatpoint but the gradual narrowing of the space between the driving-pulleysprevents t-he needle from so creeping, excepting at first and to a verylimited extent, depending on itsconvolutions becoming slightly smallerin consequence of its elasticity.

In the accompanying drawings, Figure 1 is a front elevation of theentire machine. Fig. 2 is an enlarged plan of the needledriving part-s.Fig. 3 is a sectional end elevation corresponding to Fig. 2. Fig. 4 is afront elevation of the needle, and Fig. 5 is a sectional elevation ofone of the drivingpulleys with its bevel-wheel.

The needle 6 is in the form of a left-hand conical helix of a littlemore than two convolutions, and is placed with its axis in a horizontalplane, and with its larger convolution and pointed end toward the lefthand, the hook or eye for the thread being at its other or right-handend. The cloth or sacking to be seamed or overcast is moved along fromleft to right upon a ledge or narrow table, 7, its right-hand end beingentered under the lefthand end of a long narrow presser-foot, 8. Thefeed motion of the cloth is continuous, being produced by an endlesschain, partly indicated at 9 in Fig. 1. The needle leads the thread downthroughthe cloth and brings it up round the edge, and each loop orstitch is also carried round what is known as the thread-barrel, 10,which extends through the center of the needle. My invention has nothingto do with this thread-barrel or its driving or other details; but itmaybe briefly explained that the barrel rotates with a surface speedsomewhat greater than that of the needle, and acts frictionally on theloops of thread, so as to help the thread forward after the needle. Oncommencing a scam, the barrel 10 projects to the right hand from theneedle to an extent corresponding to the length of scam, and the loopsmove along (with the cloth) to its right-hand end, on reaching whichthey slip off in succession, while the barrel then moves slowly backwardor toward the left hand. The rate of the progressive motion of the clothand that of the backward movement of the barrel are such that thestitches in the cloth become tightened to the desired degree as theysuccessively pass forward beyon the end of the barrel.

The needle 6 is placed between three conical helically-grooveddriving-pulleys, 11 12 13, the middle one, 12, behind the needle, havingits axis in the same horizontal plane as the needle, and being fixed onaspindle,14,which is driven by means of bevel-wheels 15 16 from thefirst-motion shaft 17 of the machine. On the spindle 11 of the middlepulley, 12, there is also fixed a toothed bevel-wheel, 18, which,

through intermediate bevel-wheels, 19 20,

drives bevel-wliecls 21 22, fixed to the upper and lower pulleys, 11 13.The pulleys 11 12 13 and bevel-wheels 18 19 2O 21 22 are carried by astandard, 23, partly in the form of part of a spherical shell, all butthe middle pulley, 12, and its bevel-wheel 18 being on studs. The studof the top pulley, 11, is movable, being held in its place by a hingedcover, 24, secured by a screw, 25, while the back of the stud is fittedto an arm, 26, which is centered on the stud of the intermediatebevelwheel 19 made to project at the back for the purpose. XVhen thecover 24: is opened, the top pulley, 11,with its bevel-wh eel 21, can beturned over; but the arm 26 makes the bevel-wheel 21 keep in gear withthe intermediate bevel-wheel 19, and thereby prevents the pulley 11 frombeing turned into a wrong position relatively to the other pulleys, 1213. The top pulley, 11, is made movable in this way to give access forplacingor removing the needle 6. The front line of the horizontalsection of the cone ol' the needle has necessarily to coincide with theline of stitehingthat is, of the holes made successively in the clothandas the said line must pass through the apex of the cone, it follows thatthe point to which the axes of the needle and its driving-pulleysconverge is in the line of stitching. It also follows that the axis ofthe needle, which axis is also the center line of the group of pulleysand their bevel-wheels, is not at right angles to the plane ofprojection of Fig. 3, and allowance must be made for this in judging oftheir positions from that figure.

\Vhat I claim as my invention is A sewing-machine having a needle in theform of a conical helix, and conical helicallygrooved pulleys supportingand adapted to drive said needle, substantially as described. I Intestimony whereof I havesigned my name to this specification in thepresence of two subscribing witnesses.

EDMUND HUNT. lVitnesses:

Rom. KINNIBURGH, D. FERGUSON.

